Power is a quality that is associated with speed of movement. In tennis, the emphasis is on the “first step” and quick change-of-direction, early set-up, etc. All of these terms relate to the ability of the player to overcome the inertia of their own body/weight and to initiate movement. The faster athletes do these things the more impressive they are.
The tennis players who can apply their strength most effectively are the ones who can hit the ball hardest and serve the fastest. This is why power as well as strength is important. Using a system of training known as “plyometrics” best develops power.
Plyometric drills are generally conducted as a form of “jump training”. The method of training which seeks to enhance the explosive reaction of the individual through powerful muscular contractions as a result of rapid eccentric contractions.
Plyometric training for the lower extremities is often classified according to response of ground contact times. Thus, the terminology “rapid response” and “longer response” appears in the literature.
Rapid response exercises are generally used to develop footwork drills. They are performed as brief, quick responses to the ground contact. Plyometrics that use the total lower extremity in larger amplitude movements such as jumping or bounding are intended to develop a higher degree of force and thus require longer ground contact times in order to develop these forces, and are known as “long response” jumps.
The physiological basis of plyometrics lies in what is known as “stretch-shortening” cycle of muscle activity. Muslces are designed in such a way that when rapidly stretched, they ‘rebound’ and shorten in reaction to rapid stretching.
This only occurs when the magnitude and rate of stretch is rapid and of sufficient magnitude that it will trigger this muscle action. This rebound effect allows the muscles to develop more forceful and faster contraction speeds than if they are not subjected to a stretch stimulus.
Intensity of plyomteric training
It is important to control the intensity of training by setting limits to the distance or height over which the player jumps. There is little need for vertical jumping ability in tennis, thus, most of the jumping drills will be focused on linear efforts over boxes and barriers that are not of great height. In tennis, hurdles and boxes used as barriers for training should rarely exceed 0.35-0.4m in overall height
The energy system most likely to be involved in tennis training using plyometrics will be the ATP-PCr system. This system requires exercise effort to be maximal and last (duration) from 1-15 seconds.
The utilisation of oxygen is too slow to meet the demands of this type of activity and the energy stores in the muscles (ATP and creatine phosphate) are utilised rapidly until they are exhausted and the muscles cannot function. Therefore, rest ratios should allow for energy replenishment and require much longer times than the work bouts. Work to rest ratios are generally considered to be 1:5 – 1:10
If the exercise lasts longer than 15 seconds and up to 60 seconds, then anaerobic glycolysis may be utilised.
In this situation the cardiovascular system still cannot utilise oxygen adequately. Therefore, an oxygen debt is encountered and energy is derived from both the ATP-PCr system and anaerobic glycolysis.
Work:rest ratios in this form of training are also usually 1:2 – 1:6
Volume of Plyometric Training
The number of “reps” and “sets” utilised in plyometric training for tennis will depend on the age of the player. Young athletes, inexperienced as weight trainers, benefit from motor learning and recovery.
Therefore, they should do fewer drills and be taught to do them correctly. Even a simple task such as jumping to the top of a 0.3m box requires some learning of body mechanics to correctly take-off and then land on an elevated surface
||Number of Exercises
The most successful plyometric drills in working with tennis players are those that are specifically related to the game itself. Plyometric exercises are centred on reducing ground contact time. In order to develop faster reactions to landing and getting off the ground a certain amount of learning should occur. It is advisable to allow players to perform a “warm-up” set of exercises at less than all-out effort prior to focusing on maximum efforts.
Exercise 1: Jump to Box
To develop lower extremity power.
The player stands with their feet shoulder width apart 03-.0.45m in front of a sturdy box, 0.3-0.6m high. The player jumps vertically as high as he can and lands on the box. His entire feet should be on the box at landing. The player should then step off the box and repeat for the required number of repetitions.
Control the landing; land softly! Finish with entire feet on the box.
Exercise 2 : Split Squat Jump
To improve hip flexibility and hip flexor power.
The player assumes a split squat position with one foot forward and the other projected to the rear. Hands can be placed on the hips. In this position the front knee will be bent at 90° and the rear knee will be almost touching the ground. The player will jump as high as possible and switch the position of the legs before landing.
Focus on the landing and maintain the torso in an upright posture.
Exercise 3 : Side-to-side Box Shuffle
To improve the ability to push-off the ground in a lateral direction.
The player stands next to a sturdy box approximately 0.5m wide and 0.3m high. The player places their right foot on the box while the left foot remains on the ground. The player then pushes up and across the top of the box; landing with the let foot in the middle of the top of the box and the right foot on the ground. Continue to shuffle back and forth across the box for the prescribed number of repetitions.
The player should use their arms to facilitate their lifting from the ground. Land softly and control the landing. Try to move back and forth in a smooth manner.
Exercise 4 : Lateral Cone Hop
To improve the player’s reactivity to the ground.
Line up 5-6 cones (0.3-0.35m high), spaced 0.6-0.9m apart. The player stands with their side at one end of the line of cones. The player then jumps sideways over the cones landing on both feet until they reaches the last cone. At the last cone the player lands on a single foot (outside leg) and immediately pushes back repeating the exercise in the opposite direction.
Smaller cones should be used when the player first performs the drill. The player should try and jump back and forth an odd number of times (3-5) so that they have an equal number of single foot landings at the ends.